// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_VIEWS_CONTROLS_TABLE_TABLE_HEADER_H_
#define UI_VIEWS_CONTROLS_TABLE_TABLE_HEADER_H_

#include "base/macros.h"
#include "ui/gfx/font_list.h"
#include "ui/views/view.h"
#include "ui/views/views_export.h"

namespace views {

class TableView;

// Views used to render the header for the table.
class VIEWS_EXPORT TableHeader : public views::View {
public:
    // Internal class name.
    static const char kViewClassName[];

    // Amount the text is padded on the left/right side.
    static const int kHorizontalPadding;

    // Amount of space reserved for the indicator and padding.
    static const int kSortIndicatorWidth;

    explicit TableHeader(TableView* table);
    ~TableHeader() override;

    const gfx::FontList& font_list() const { return font_list_; }

    // views::View overrides.
    void Layout() override;
    void OnPaint(gfx::Canvas* canvas) override;
    const char* GetClassName() const override;
    gfx::Size GetPreferredSize() const override;
    gfx::NativeCursor GetCursor(const ui::MouseEvent& event) override;
    bool OnMousePressed(const ui::MouseEvent& event) override;
    bool OnMouseDragged(const ui::MouseEvent& event) override;
    void OnMouseReleased(const ui::MouseEvent& event) override;
    void OnMouseCaptureLost() override;
    void OnGestureEvent(ui::GestureEvent* event) override;

private:
    // Used to track the column being resized.
    struct ColumnResizeDetails {
        ColumnResizeDetails()
            : column_index(0)
            , initial_x(0)
            , initial_width(0)
        {
        }

        // Index into table_->visible_columns() that is being resized.
        int column_index;

        // X-coordinate of the mouse at the time the resize started.
        int initial_x;

        // Width of the column when the drag started.
        int initial_width;
    };

    // If not already resizing and |event| is over a resizable column starts
    // resizing.
    bool StartResize(const ui::LocatedEvent& event);

    // Continues a resize operation. Does nothing if not in the process of
    // resizing.
    void ContinueResize(const ui::LocatedEvent& event);

    // Toggles the sort order of the column at the location in |event|.
    void ToggleSortOrder(const ui::LocatedEvent& event);

    // Returns the column to resize given the specified x-coordinate, or -1 if |x|
    // is not in the resize range of any columns.
    int GetResizeColumn(int x) const;

    bool is_resizing() const { return resize_details_.get() != NULL; }

    const gfx::FontList font_list_;

    TableView* table_;

    // If non-null a resize is in progress.
    scoped_ptr<ColumnResizeDetails> resize_details_;

    DISALLOW_COPY_AND_ASSIGN(TableHeader);
};

} // namespace views

#endif // UI_VIEWS_CONTROLS_TABLE_TABLE_HEADER_H_
